US4082997A - Oil detecting device - Google Patents

Oil detecting device Download PDF

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Publication number
US4082997A
US4082997A US05/589,538 US58953875A US4082997A US 4082997 A US4082997 A US 4082997A US 58953875 A US58953875 A US 58953875A US 4082997 A US4082997 A US 4082997A
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US
United States
Prior art keywords
oil
water
detecting element
particle layer
oil detecting
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US05/589,538
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English (en)
Inventor
Takao Ohtsu
Yukinobu Nakamura
Akira Sugimoto
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
JGC Corp
Original Assignee
Japan Gasoline Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Japan Gasoline Co Ltd filed Critical Japan Gasoline Co Ltd
Application granted granted Critical
Publication of US4082997A publication Critical patent/US4082997A/en
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
    • G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
    • G01R27/22—Measuring resistance of fluids
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/02—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance
    • G01N27/04—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance
    • G01N27/12—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance of a solid body in dependence upon absorption of a fluid; of a solid body in dependence upon reaction with a fluid, for detecting components in the fluid

Definitions

  • This invention relates to an oil detecting element and an oil detector incorporating the oil detecting element suitable for detecting oil floating on water such as oil floating on a river, lake, or sea, or sewer in the oil refineries, chemical factories etc. and oil leaking in an underground pipeline.
  • This device is disadvantageous, however, in that the conductive organic material which is formed by mixing a powdered conductive material into an organic material and thereafter solidifying them together is not sufficiently permeable to oil and, accordingly, response to the change in electric resistance at the time of contact between oil and the material is so slow and the value of change is too small that application of this prior art device is limited to detection of oil leakage in a pipeline where a large amount of leaking oil is present. Furthermore, the prior art device is defective in that no consideration is given to elimination of water which tends to contact the detector so that conductivity of the conductive organic material tends to increase when water comes into contact with the material notwithstanding the fact that the material is in contact with oil. This apparently offsets change in electrical resistance with a resulting inaccuracy in detection.
  • an object of the present invention to provide an oil detecting element capable of detecting oil on water with a high degree of response and sensitivity.
  • FIG. 1 is a perspective view of a preferred embodiment of the oil detecting element according to the invention.
  • FIG. 2 is a sectional view of the oil detecting element shown in FIG. 1;
  • FIG. 3 is a sectional view of another embodiment of the oil detecting element according to the invention.
  • FIG. 4 is a circuit diagram showing an example of oil detector incorporating the oil detecting element.
  • FIG. 5 is a circuit diagram showing another example of oil detector incorporating the oil detecting element.
  • the oil detecting element comprises a casing 1 which has an opening 1a on one side thereof.
  • a filtering member 2 made of water-repellent, oil-passing material is mounted in this opening 1a.
  • the casing 1 consists of a rigid or soft non-conductive material such as plastics.
  • the casing 1 is bonded or otherwise connected watertight to the member 2 at an end portion a thereof to prevent water from coming into the opening 1a.
  • the water-repellent, oil passing filtering member 2 is made of a material which passes oil and repels water such as synthetic resin filaments or natural fibre coated with resin. Accordingly, water is prevented from coming into the casing 1 and only oil passes through the member 2.
  • a conductive particle layer 4 is provided on the rear inner side of the member 2.
  • This conductive particle layer 4 is provided at opposite ends thereof with electrodes 3a and 3b which project outwardly from the casing 1 and are used as connecting terminals.
  • the conductive particles of the layer 4 particles of a suitable conductive materials such, for example, as metals, metal oxides and carbon.
  • the conductive particle layer may be formed either by sealing the conductive particles in the opening 1a or by coating a base member 5 made of a suitable insulating material with the conductive particles.
  • the layer 4 may also be formed by coating the rear surface of the member 2 with the conductive particles.
  • the conductive particle layer need not be a thick one but a layer in which each particle is in contact with an adjacent particle between the electrodes 3a and 3b will suffice.
  • the layer 4, however, should preferably be in close contact with the above described member 2.
  • the layer 4 is in the form of particles so that oil rapidly reaches between the particles. Accordingly, the oil detecting element according to the invention sharply responds to an extremely small quantity of oil, e.g. in the order of few ⁇ l, and produces a relatively large change in the value of electric resistance.
  • a result of an experiment which was conducted by introducing 100 ⁇ l of Agha jari crude oil in the inventive oil detecting element shows that resistance increased from an initial value of 6.8 to 80 K ⁇ in a matter of few seconds. It will be understood from this result that the inventive oil detecting element has sufficiently high response characteristics and sensitivity and change in resistance is remakably large. The value of resistance further increases as time elapses after the initial contact between oil and the conductive particle layer 4.
  • the oil detecting element according to the invention presents a sufficiently large change in electric resistance at the initial contact with oil and a still larger change after a lapse of several seconds. This enables the oil detecting element to perform oil detection immediately upon its initial contact with oil.
  • a material which has a large water repelling property e.g. polyflon or silicon resin, will be particularly useful as the member 2 in detecting oil floating on water which has a relatively great conductivity such as sea water.
  • FIG. 3 shows another embodiment of the oil detecting element according to the present invention.
  • This figure is a sectional view of the oil detecting element substantially constructed in the form of a sheet.
  • a conductive particle layer 4 is coated on the rear surface of a water-repellent member 2 and this member 2 is enclosed watertight in a sheet 6 which is made of a heat melting material.
  • the sheet 6 has an opening 1a in which the outer surface of the member 2 is exposed.
  • the conductive particle layer 4 is provided at opposite ends thereof with electrodes 7a and 7b consisting of pieces of metal foil. These electrodes 7a and 7b are bonded to the layer 4 and are projecting out of the lower surface of the sheet 6.
  • This embodiment is a compact construction compared with the previously described embodiment and the member 2 and the conductive particle layer 4 used in the previously described embodiment may be effectively used in the present embodiment.
  • water life such as algae and shells tend to settle and grow on the surface of the oil detecting element with a resultant lowering of detecting efficiency. It is therefore necessary in such cases to provide means for preventing settling of water life on the surface of the oil detecting element.
  • another embodiment of the present invention uses a water-repellent member containing a material which is toxic to the water life.
  • any material among organic chlorides may be used as long as it is poisonous to the water life and hard to dissolve in water.
  • pentachlorophenol-2,3-dichloro-1,4-nephthoquinone may be effectively used as this material.
  • oleophilic and water-repellent properties of the water-repellent member are not hampered by including the above described toxic material in the member.
  • the toxic material must be hard to dissolve in water because otherwise the material will be rapidly dissolved by water and will not be able to prevent settling of the water life on the surface of the oil detecting element. If the material is hard to dissolve in water, it will dissolve only gradually and prevent settling of the water life which tend to settle on the surface of the oil detecting element. Contents of the toxic-material in the order of 0.5-5 wt % in the entire member 2 will be sufficient to preventing settling of the water life.
  • FIGS. 4 and 5 show examples of an oil detector which employs one of the above described oil detecting elements.
  • the oil detector comprises an oil detecting element K, a detection circuit EB which detects change in resistance of the oil detecting element K and produces a detection signal and an alarming circuit ES which is actuated by this detection signal.
  • a bridge circuit is used as the detection circuit EB. More specifically, resistors R 1 -R 3 and the oil detecting element K are connected in bridge connection, a power source E 1 is connected between connection points P and O, and a connection point between the resistor R 2 and the oil detecting element K is connected to the gate of a silicon control rectifier S 1 .
  • the alarming circuit ES and a power source E 2 are connected in series to the silicon control rectifier S 1 .
  • the alarming circuit ES a known circuit such, for example, as one for actuating a buzzer or lighting a lamp or a transmitter may be effectively employed.
  • the alarming curcuit ES is provided for informing a watchman in a remote place of detection of oil on water.
  • FIG. 5 shows another example of the oil detector incorporating the oil detecting element.
  • a differential amplifier OP 1 constructed of an integrated circuit is used as a detection circuit EB, an oil detecting element K is provided in a feed-back circuit of this differential amplifier OP 1 .
  • These circuits as a whole constitute a non-phase-inverting amplifier.
  • values of resistance of input resistors R 4 and R 5 are selected at such ones that the amplifier OP 1 will not emit a detection signal when no oil is detected.
  • Reference characters VR designate a variable resistor provided for adjusting sensitivity of the oil detector.
  • voltage across the oil detecting element K can be of a relatively small value (e.g., 0.3V). Accordingly, this oil detector is advantageous in that no electrolysis takes place even if water should come into the oil detecting element and therefore the oil detector can enjoy a longer life.
  • Each of the specimens of the oil detecting element was attached to a buoy in such a manner that the surface of the oil detecting element (i.e. the surface of the water-repellent member) would intersect at right angles with the surface of water and this buoy was floated on one end region of a seawater pool of 1 by 4 m in such a manner that about half of the surface of the oil detecting element would submerge below the surface of water. Crude oil of about 10 ml was quietly dropped on the other end region of the seawater pool.
  • An oil detecting element which is identical with the specimen A of the above described first example was used with kerosene instead of crude oil.
  • the value of resistance of this element initially was 8.3 K ⁇ and it increased to 21 K ⁇ when 10 seconds elapsed after the oil film reached the surface of the element.
  • a test similar to the first example was conducted by using a specimen which was identical with the above described specimen A. This test was conducted in fresh water instead of seawater. The resistance changed from the initial value of 8.0 to 120 K ⁇ when 10 seconds elapsed after the oil film reached the surface of the element.
  • Organic chlorides shown in the following Table II were dissolved in a suitable organic solvent such as alcohol or benzene to make solution of about 2%.
  • a member made of a polyflon unwoven cloth with dimensions of 1 by 4 cm was dipped in the solution for about one to five minutes and it was dried thereafter. This operation was repeated two or three times to make water-repellent members respectively containing one of the organic chlorides. Content of the organic chloride in the filter was about 1 wt %.
  • Specimens of the member were soaked in a beaker in which a heavy oil film was formed on water to examine permeability of water and that of oil.
  • the oil detecting element according to the present invention is not limited to the construction and shape shown in the accompanying drawings but any construction or shape may be employed as long as the water-repellent filter passes oil only to allow it to come into contact with the conductive particle layer with a resultant change in electric resistance of the element.
  • the oil detecting element and the oil detector incorporating the oil detecting element according to the invention may be employed in all regions including rivers, lakes, seas, sewer in the oil refineries etc. and underground pipelines. If, for example, the oil detecting element or the oil detector is to be used for detecting exhaust oil floating on the sea, several pieces of the oil detecting element or the oil detector are disposed in desired detection places such as an entrance of a bay.
  • the oil detecting elements or the oil detectors should be floated on water in such a manner that the water-repellent member will easily come into contact with the floating oil.
  • the oil detecting elements or the oil detectors thus provided on water are expected to detect oil rapidly and prove very useful for preventing water pollution which will cause a great damage to sea-products etc.
  • the inventive oil detecting element or oil detector is used in an underground pipeline, it will accurately detect the smallest quantity of leaking oil without being affected by water coexisting with oil. It will be understood that the oil detecting element or oil detector can detect not only mineral oils but other kinds of oils including animal and plant oils.

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  • General Physics & Mathematics (AREA)
  • Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Biochemistry (AREA)
  • Immunology (AREA)
  • Electrochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • Pathology (AREA)
  • Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
  • Investigating Or Analyzing Materials By The Use Of Fluid Adsorption Or Reactions (AREA)
US05/589,538 1974-06-25 1975-06-23 Oil detecting device Expired - Lifetime US4082997A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP49073047A JPS512490A (es) 1974-06-25 1974-06-25
JA49-73047 1974-06-25

Publications (1)

Publication Number Publication Date
US4082997A true US4082997A (en) 1978-04-04

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US05/589,538 Expired - Lifetime US4082997A (en) 1974-06-25 1975-06-23 Oil detecting device

Country Status (7)

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US (1) US4082997A (es)
JP (1) JPS512490A (es)
CA (1) CA1042682A (es)
DE (1) DE2528026A1 (es)
FR (1) FR2276584A1 (es)
GB (1) GB1509602A (es)
NL (1) NL7507451A (es)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2900764A1 (de) * 1978-01-10 1979-07-12 Asahi Chemical Ind Verfahren zur ultrafiltration von oelhaltigen fluessigkeiten
US4273650A (en) * 1979-01-10 1981-06-16 Emtek Incorporated Apparatus and method for recovering pollutant liquids
US4644263A (en) * 1984-12-13 1987-02-17 Marathon Oil Company Method and apparatus for measuring water in crude oil
US4862066A (en) * 1987-08-31 1989-08-29 Junkosha Co., Ltd. Oil leakage sensor element
US5378995A (en) * 1992-03-05 1995-01-03 Mitsubishi Cable Industries, Ltd. Low molecular weight organic liquid detection sensor in the shape of a wire and detector using this sensor
US5591901A (en) * 1994-04-13 1997-01-07 Ryland Engineering Corporation Fluid sensor
WO2005098419A1 (de) * 2004-04-06 2005-10-20 Testo Ag Messvorrichtung zur messung des zustands von ölen oder fetten
JP2008539397A (ja) * 2005-04-28 2008-11-13 フォルシュングスツェントルム・ドレスデン−ロッセンドルフ・アインゲトラーゲナー・フェライン グリッドセンサー
US20110084708A1 (en) * 2008-05-13 2011-04-14 Steven Yu Apparatus, devices, systems, kits, and methods of monitoring food treating media
US8564310B2 (en) 2009-08-18 2013-10-22 3M Innovative Properties Company Capacitive oil quality monitoring sensor with fluorinated barrier coating
KR20230133568A (ko) * 2022-03-11 2023-09-19 한국전력공사 유중수분 측정장치, 이를 이용한 측정방법과, 유중수분 농도검출방법

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6020043Y2 (ja) * 1975-09-27 1985-06-15 新コスモス電機株式会社 遅延形油分検知素子
JPS56141374A (en) * 1980-04-05 1981-11-05 Hayakawa Rubber Co Ltd Water cut-off material composition
JPS5785500A (en) * 1980-11-14 1982-05-28 Hayakawa Rubber Moisture swelling water stopping material and water stopping method thereof
JPS5768437A (en) * 1980-10-17 1982-04-26 Hayakawa Rubber Water swellable water stopping material and method
US4361031A (en) * 1980-10-17 1982-11-30 Emhart Industries, Inc. Sensing device
JPS5770175A (en) * 1980-10-17 1982-04-30 Hayakawa Rubber Co Ltd Water-swelling, water-stoppable material composition
GB2120389A (en) * 1982-04-28 1983-11-30 Anthony John Maxwell Monitoring lengths of hose
JPS62252475A (ja) * 1986-04-24 1987-11-04 Matsushita Electric Works Ltd 塗料組成物
JPH01148934A (ja) * 1987-12-04 1989-06-12 Junkosha Co Ltd 漏洩検出装置
JPS63308081A (ja) * 1988-02-05 1988-12-15 Hayakawa Rubber Co Ltd 水膨潤性止水材

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3019904A (en) * 1959-08-14 1962-02-06 Edward B Stecher Aviation fuel filter
US3096204A (en) * 1958-12-29 1963-07-02 Spangler Method of making a coated fibrous filter element
US3229817A (en) * 1962-05-31 1966-01-18 Pall Corp Assembly for separating immiscible fluids
US3242073A (en) * 1963-03-07 1966-03-22 Dow Chemical Co Removal of microorganisms from fluids
US3395802A (en) * 1966-12-16 1968-08-06 Rosaen Filter Co Fluid filter condition indicators
US3462362A (en) * 1966-07-26 1969-08-19 Paul Kollsman Method of reverse osmosis
US3719936A (en) * 1971-06-01 1973-03-06 Durham Ass Inc Oil spillage detection system
US3847810A (en) * 1973-05-04 1974-11-12 A Tulumello Apparatus for separating oil from water and measuring the amount of oil so separated
US3860517A (en) * 1973-06-15 1975-01-14 Betz Laboratories Slime control compositions and their use
US4008619A (en) * 1975-11-17 1977-02-22 Mks Instruments, Inc. Vacuum monitoring

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS586147B2 (ja) * 1973-09-01 1983-02-03 ホツカイドウデンリヨク カブシキガイシヤ アブラケンチソシ
JPS5741491Y2 (es) * 1977-06-30 1982-09-11

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3096204A (en) * 1958-12-29 1963-07-02 Spangler Method of making a coated fibrous filter element
US3019904A (en) * 1959-08-14 1962-02-06 Edward B Stecher Aviation fuel filter
US3229817A (en) * 1962-05-31 1966-01-18 Pall Corp Assembly for separating immiscible fluids
US3242073A (en) * 1963-03-07 1966-03-22 Dow Chemical Co Removal of microorganisms from fluids
US3462362A (en) * 1966-07-26 1969-08-19 Paul Kollsman Method of reverse osmosis
US3395802A (en) * 1966-12-16 1968-08-06 Rosaen Filter Co Fluid filter condition indicators
US3719936A (en) * 1971-06-01 1973-03-06 Durham Ass Inc Oil spillage detection system
US3847810A (en) * 1973-05-04 1974-11-12 A Tulumello Apparatus for separating oil from water and measuring the amount of oil so separated
US3860517A (en) * 1973-06-15 1975-01-14 Betz Laboratories Slime control compositions and their use
US4008619A (en) * 1975-11-17 1977-02-22 Mks Instruments, Inc. Vacuum monitoring

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2900764A1 (de) * 1978-01-10 1979-07-12 Asahi Chemical Ind Verfahren zur ultrafiltration von oelhaltigen fluessigkeiten
US4273650A (en) * 1979-01-10 1981-06-16 Emtek Incorporated Apparatus and method for recovering pollutant liquids
US4644263A (en) * 1984-12-13 1987-02-17 Marathon Oil Company Method and apparatus for measuring water in crude oil
US4862066A (en) * 1987-08-31 1989-08-29 Junkosha Co., Ltd. Oil leakage sensor element
US5378995A (en) * 1992-03-05 1995-01-03 Mitsubishi Cable Industries, Ltd. Low molecular weight organic liquid detection sensor in the shape of a wire and detector using this sensor
US5591901A (en) * 1994-04-13 1997-01-07 Ryland Engineering Corporation Fluid sensor
US5642053A (en) * 1994-04-13 1997-06-24 Heckman; James R. Fluid identification sensor
US20080186033A1 (en) * 2004-04-06 2008-08-07 Mike Muhl Measuring Device For Measuring the State of Oils or Fats
WO2005098419A1 (de) * 2004-04-06 2005-10-20 Testo Ag Messvorrichtung zur messung des zustands von ölen oder fetten
US7652490B2 (en) 2004-04-06 2010-01-26 Testo Ag Measuring device for measuring the state of oils or fats
JP2008539397A (ja) * 2005-04-28 2008-11-13 フォルシュングスツェントルム・ドレスデン−ロッセンドルフ・アインゲトラーゲナー・フェライン グリッドセンサー
JP4654293B2 (ja) * 2005-04-28 2011-03-16 フォルシュングスツェントルム・ドレスデン−ロッセンドルフ・アインゲトラーゲナー・フェライン グリッドセンサー
US20110084708A1 (en) * 2008-05-13 2011-04-14 Steven Yu Apparatus, devices, systems, kits, and methods of monitoring food treating media
US8564310B2 (en) 2009-08-18 2013-10-22 3M Innovative Properties Company Capacitive oil quality monitoring sensor with fluorinated barrier coating
KR20230133568A (ko) * 2022-03-11 2023-09-19 한국전력공사 유중수분 측정장치, 이를 이용한 측정방법과, 유중수분 농도검출방법
KR102659944B1 (ko) 2022-03-11 2024-04-24 한국전력공사 유중수분 측정장치, 이를 이용한 측정방법과, 유중수분 농도검출방법

Also Published As

Publication number Publication date
CA1042682A (en) 1978-11-21
GB1509602A (en) 1978-05-04
NL7507451A (nl) 1975-12-30
FR2276584B3 (es) 1979-02-16
DE2528026A1 (de) 1976-01-15
JPS512490A (es) 1976-01-10
FR2276584A1 (fr) 1976-01-23

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